Untrue. I lived and worked as a software engineer in Chicago (downtown) for a number of years before moving westward. Most mid-career developers I knew there were comfortably in the 100's and only one worked at the CME ('finance stuff', in C++).

It boils down to simple economic rules. If you're good at developing software, there aren't a lot of people like you looking for a job and the market has a high demand for your skill then you are probably doing something wrong if you're not earning well into the 100's or higher (if that is what you're trying to optimize for).

I've seen companies willing to pay >100k in Chicago and relocate people there, for engineers with only ~4 years of experience.